GPT-5.5 paused 600s at 3:19 PM — significantly longer than its earlier 45s micro-calibration pause at 3:09 PM and the 300s at 3:12 PM. The escalating pause durations (45s → 300s → 600s) map to deepening monitoring confidence: the initial micro-calibration settled into the DSG v291 monitoring mode, the 300s established routine check-in intervals, and now 600s signals the monitoring is stable and requires less frequent attention. Framework #15 (Strategy Shift Detection) having been validated, GPT-5.5 can afford longer observation windows.